Joseph thomas



J. THOMAS.

Furnacefor Tampering Steei Springs.

No. 22.041. Patented Nov. 9; 1858.

UNITED STATES PATENT OFFICE.

JOSEPH THOMAS, OF NEW l'Oliii, N. Y.

FURNACE FOR TEMPERING STEEL.

Specification of Letters Patent No. 22,041, dated November 9, 1858.

To all whom it may concern:

Be it known that I, JOSEPH THOMAS, of the city, county, and State of NewYork, have invented certain new and useful Improvements in Furnaces forTempering Steel Springs; and I do hereby declare that the following is afull, clear, and exact description of the same, reference being had tothe annexed drawings, making a part of this specification, in which-Figure 1, represents a plan or top view of my furnace. Fig. 2, is a sideelevation of the same. Fig. 3, is an end elevation of the same. 7

Similar letters of reference indicate corresponding parts in the severalfigures.

This invention consists in passing the steel wire or strip of sheetsteel which is intended to be tempered, and the length of which may beindefinite, through an opening in a plate of fire clay, or of cast iron'which is exposed to a well regulated fire from both sides, in anupright furnace which is placed over a tank containing water 01' otherliquid suitable for hardening steel, so that the Wire or strip of sheetsteel becomes heated to the proper degree without coming in contact withthe fire, and that the same when so heated may be passed through thetank containing the liquid in order to harden it; said tank being placedin such relation to an additional furnace which serves to heat two thickplates of cast iron or other suitable material that the steel wire onstrip of sheet steel may be passed from the tank between the two heatedplates, so

that the same receives the proper temper, the whole being so arranged,that the steel wire or strip of sheet steel is hardened and tempered atone operation.

To enable others skilled in the art to fully understand and construct myinvention, I will proceed to describe it.

A, is an upright furnace which is divided into two compartments by avertical plate 13, made of fire clay or cast iron or other suitablematerial, and C, is the fire grate which is situated in the lower partof the furnalce, so that a fire built on the grate heats the plate B,from top to bottom. In the center of this plate is a vertical passage a,open at both ends so that a piece of steel wire or strip of sheet steelmay be passed through the same.

D, is a tank containing water or other suitable liquid for hardeningsteel, and a roller Z), is arranged in this tank and under the passage61, so that the steel wire or strip of sheet steel, intended fortempering, as it runs out of the passage (4, may be passed under theroller Z), and through the liquid in the tank D, the quantity of whichmust be such as to reach at least to the center of the roller Z). Bythus passing the steel wire or strip of sheet steel through the passagea, it becomes heated without coming in immediate contact with the fire,which in itself is a great advantage, as steel is damaged in all caseswhere it is brought in immediate contact with the fire before it is hardened, and the fire in the furnace must be so regulated and the speedwith which the steel wire or strip of sheet steel is passed through thepassage a, must be such that the same is heated to the propertemperature before it enters the tank containing the liquid. Thetemperature to which steel is to be heated, in order to harden the same,depends upon the quality of the steel used and must therefore bedetermined in each case by actual experiment.

An additional furnace E, is arranged in close proximity to the tank D,and this furnace is covered with a plate, F, of cast iron or othersuitable material, which is provided with a projecting rim (Z, betweenwhich another plate, G, fits easily. That part of the rim (Z, facingtoward and from the tank D,

is partly removed, see Fig. 1. This furnace is provided with a separategrate and two openings 6, e, are made in the sides of the same wherebythe draught of the fire may be regulated. The plate F. and G, may thusbe heated to any desired degree and by passing the steel wire or stripof sheet steel as it comes from the tank 1), between the two plates F,and G, the temper required for a good spring will be given to the same,if the temperature of the two plates and the speed with which the steelwire or strip of sheet steel is passed between the same is properlyregulated. Any length of steel wire or a strip of sheet steel ofindefinite length may thus be hardened and tempered by one operation, byfirst bringing both furnaces to the proper temperature and passing theend of the steel through the passage to, and under the roller Z), andbetween the plates F, and G, and drawing the same through with a speedwhich depends upon the respective heat of the two furnaces.

Having thus described my invention, What- I claim as new and desire tosecure by Letters Patent, is

1. Arranging a plate B, in an upright furnace with a central passage a,in such a manner and in such relation to a tank D, containing water orother suitable liquid that a piece of steel wire or a strip of sheetsteel may be heated and hardened without coming in immediate contactwith the fire by passing the same through the passage a, and through theliquid contained in the tank I D, the Whole being arranged substantiallyf as specified.

2. And I also claim arranging the two furnaces A, and E, and the tank D,in such relation to each other that a piece of steel wire or a strip ofsheet steel may be hardened and tempered by one operation, by passingthe same through the plate B, in the furnace A, and through the liquidcontained in the tank D, and from thence between the plates F and G,which are heated by the fire in the furnace E, the whole being arrangedand constructed substantially as described.

JOSEPH THOMAS. Witnesses:

S. H. \VALEs, JAMES G. COOPER.

